1. Field of the Invention
This invention relates to the purification of hepatitis B surface antigen. More especially this invention relates to a purification of such hepatitis B surface antigen by removal therefrom of other components which are in admixture therewith. This invention is particularly concerned with the selective removal of hepatitis B surface antigen from other proteinaceous material in a blood fraction or in human serum.
2. Discussion of the Prior Art
Numerous attempts have been made to purify hepatitis B surface antigen. These attempts have been made since a prerequisite for a vaccine is a purified hepatitis B surface antigen. The purification of hepatitis B surface antigen has taken a number of routes. One of such routes involves the use of immunosorbents. These immunosorbents represent the most selective tool for the isolation and purification of antigens. However, their use in large purification is not a practical route inasmuch as the supply of mono-specific antibodies may be limited.
As a result thereof, chromatographic techniques based on less specific interactions that those involved in immunologic recognition has proved to be advantageous for the separation of virus antigens from contaminating proteins. One approach to the purification of hepatitis B surface antigen has been to utilize a lectin, concanavalin A which has been insolubilized on agarose gel. Thus, there is described in Neurath, A. R.; Prince, A. M.; and Lippin, A. (1973) Affinity chromatography of hepatitis B antigen on concanavalin A linked to Sepharose, Journal of General Virology 19, 391-395. The Separation of Hepatitis B surface antigen from human serum has been achieved by isopycnic and rate zonal centrifugations-techniques requiring expensive equipment. Gerin, J. L.; Holland, P. V.; and Purcell, R. H. (1971): Australia antigen: Large scale purification from human serum and biochemical studies of its proteins; Journal of Virology I, 569-576.
In search for alternative techniques which are more amenable to a scaling up of the separation technique, attention has been directed to hydrophobic chromatography. Hydrophobic chromatography has been employed in the separation of proteins differing in frequency and size of exposed hydrophobic regions (Shaltiel & Er-El (1973). Hydrophobic chromatography: Use for Purification of Glycogen Synthetase. Proceedings of the National Academy of Sciences of the United States of America 70, 778-781. It became desirable to provide a process which is useful in large scale purification of hepatitis B antigen and to provide a process which would substantially further purify and concentrate hepatitis B surface antigen which had previously undergone a separation technique such as by the use of insolubilized concanavalin A or by treatment with polyethylene glycol.